but is it worth it?

I lived with my man for 6 motnhs, not really that long when I think about it. About 2 months ago I went off sex, cause of the stress caused by his wild spending, and feeling like a maid.

He understood at the time. Then he started spending a lot of time "working on his car", when he was really meeting with a 15 year old.

We split last week, he said it was cause we never did anything together anymore. HOW THE HELL COULD WE! HE SPENT ALL HIS TIME AWAY FROM ME!

I suggested some time away from each other, then try again. but he said no.

|He is now trying to get with this 15 year old, who has told him she only wants 2 b friends with him. His reply to that was "we'll see"

I want to hurt him the way he hurt me. But is it worth it? His 15 yr old and I now speak regularly, and have become friends, she was just as hurt by him as i was, he lied to her right left and center too. She wants revenge too, but how? and should we?